Molecular dynamics was used to simulate the uniaxial compression of single crystal silicon nanospheres using the Tersoff potential. The resulting yield behavior was shown to vary with changes in temperature, sphere size, and crystallographic orientation with respect to the loading direction. Only compression along the [100] crystallographic direction resulted in the formation of the β-Sn phase. A temperature dependent hardening response was observed in all orientations independent of the β-Sn phase transformation. Dislocation activity was detected at . elevated temperatures in the largest sphere indicating a critical temperature and size for nucleation. The effect of these dislocations in simulating strength properties at the nanoscale was considered.

Phase Transformations, Dislocations and Hardening Behavior in Uniaxially Compressed Silicon Nanospheres. L.M.Hale, X.Zhou, J.A.Zimmerman, N.R.Moody, R.Ballarini, W.W.Gerberich: Computational Materials Science, 2011, 50[5], 1651-60